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adjustable oscillator circuit

adjustable oscillator circuit

adjustable oscillator circuit


I'm looking for some one to build a electronics' prototype project for me or infomation that would help me buid it my-self. the prototype would be built such that it would be able to move a small 1/16th of an inch cube magnet max. 1/4 inch up and down with adjustable speed. If the length of the stroke could be changed on the prototype it would be useful in determining the best length needed.electronics' prototype

I have considered using and adjustable timer with relay outputs or a wave form generator with one of my own solenoids or small electro-magnet

I would like the magnet to move back and forth at a rate of at least 1 hz and upward to 100 mhz (or as high as possible) and work on rechargeable batteries (AA would be best).

Any ideas would be helpful.

Mike Rowley


RE: adjustable oscillator circuit

I think you are trying to do something experimentally what
you could determine theoretically to be impossible. 1/4
inch amplitude at 100 MHz would need the energy of a
powerplant and would pulverize any known material.


RE: adjustable oscillator circuit

have you thought of trying this with an electromagnet instead of a physical cube it might be more productive to just redirect the charge to different windings or is their some limitation on clearance from another object

RE: adjustable oscillator circuit

I agree that a 1/4 inch stroke at 100 mhz is impossable. I was thinking more of a strong slow stroke rate to start with that at max was 1/4 inch long, then as the speed rate increased the stroke distance would become less important. At 100 mhz the stroke could be very very very low. Thus the need for it to be ajustable in rate of ossolation.

I also agree that an electo-magnet would most likly be the best choice. The problem is I have a very limited concept of math of electronic's. Should I build some-thing based on an 1-transistor oscillator circuit or an adustable siren? Replacing the speaker with an electro-magnet? What about an clock pulse generator? or an simple LED flasher?

If you would like I could e-mail you a gif of what the circuit needs to do. It's basically a row of magnets aligned at an 45 degree angle such that north pushs against north causing them to be moved at a high rate of speed.

the pulse of the electro-magnet determaining the rate of speed.

For unrestricted conversation.
Michael Leonard Rowley

RE: adjustable oscillator circuit

I have no idea what you are trying to do.  Can you please elaborate so I (or others) can assist you with this project?


RE: adjustable oscillator circuit


  Moving a magnet back and forth should be no problem, it is basically a tuned circuit, where you would measure the current induced by the moving magnet to get resonance, but it is likely that there are more efficient solutions for a prototype, why not use the magnet+slider from an electric doorbell or something like that and just add ac voltage?

  "A row of magnets", does this mean you need one device for each magnet, or does the first arrangement activate all the other magnets? If you are trying to build a perpetuum mobile and succeed, then I want some shares :) . Just kidding, but please give some more information, and maybe we can be of some help.

RE: adjustable oscillator circuit

Hello yes way,
I have thought about useing a door-bell but I haven't gotten around to building the circit. right know I'm useing an electric tooth-brush with a small neodinium magnet glued to the end. Depending on the type and cost of the tooth-brush I can get 5000 to 36000 pulses per minite.

Unfortunitly because these tooth-brushes only have one speed I need to "push" the magnets up to the speed of the tooth-brush. If I had a way to start the pulses off slowly then increase the rate of pulses to a max speed, then slow the interval between pulses so that it mantained that speed, (yet the magnet still "pushed" at the high pulse speed) in such a way that momentium was preserved.

None of this makes sense, with-out knowing that the pulseing magnet or electro-magnet is acting upon a long row of magnets all at an 45 degree angle. Each with the same pole at the same angle. Thus when the pulseing magnet opposes the field of an magnet in the row it pushes it away.
As the pulseing magnet retreats away from the row a new magnet in the row slides into place. The magnet pulses again, the row moves again. The faster the pulses, the faster the row moves. In addition the mass of the magnets in the row must be considered, to much mass and it becomes uneconomical to run, so I'm tring to build some "uneconomical" protypes, that prove that the idea can work, then progress towards better designs.

The final purpose of this will be a sellable product so in the end it must be looking "neat and clean", and with-out an attached tooth-brush!:)

let me know what you think.

Mike R.

RE: adjustable oscillator circuit


  I would like to start by saying you will probably have no problem finding an electronic design that will suit your needs, even in full manufacturing.
  I sense that you have more information that you wish to keep for yourself at this point, and I really think you should. I still have no good grasp about the project, but I am curious of course. A simple circuit that could do for "prototype 1", can be easily built. You can email me at info.emc@telia.com if you want a simple schematic. It would also be useful to know how familiar you are with the soldering iron... :)
  Later on, as you mention, you have to take lots of things in careful consideration to find the optimal design, and it is always worth the while.
  By the way...   I think my curiosity would be greatly challenged if I saw a device with a toothbrush and lots of magnets attached on the shelves of my local supermarket... :)

RE: adjustable oscillator circuit

Mechanically this is impossible. It should be possible
to generate oscillating magnetic field with solenoid
( perhaps 2-3 for different fr.range ) with ferrit core.
Will this do ?

You can increase the current, if you connect the coil
parallel to a cap ( tank circuit)


RE: adjustable oscillator circuit


I think you are right about the solenoids, although I don't understand how I could use more then one to get a different freqency range.

I have bought a couple solenoids but haven't hooked them up to a circuit, due to lack of a ciruit design.

Is a tank ciruit only a capacitor in parallel with the coil?
Is it that simple?

RE: adjustable oscillator circuit

If I don't know what you are trying to do I can only speak
in generalities. tank = L + C .


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